Rev.2.00 Oct 16, 2006 page 125 of 354
REJ09B0340-0200
M30245 Group
2. Frequency synthesizer (PLL)
●
Frequency Multiplier
f
VCO
is generated via the Frequency Synthesizer Mul-tiply register (FSM: address 03DD
16
). When the
Frequency Multiply register is set to 255, multiplication is disabled and f
VCO
= f
PIN
. The value of n
should be set so that f
VCO
becomes 48MHz. Table 2.7.2 shows some examples of how the frequency
synthesizer multiply register is set.
f
VCO
= f
PIN
X 2(n+1)
n: FSM value
●
Frequency Divider
Clock f
SYN
is a divided down version of f
VCO
. f
SYN
is generated via the frequency synthesizer divide
register (FSD). When the frequency synthesizer divider register is set to 255, division is disabled and
f
SYN
= f
VCO
. Table 2.7.3 shows some examples of how the frequency synthesizer division register is
set.
f
SYN
= f
VCO
/ 2(m+1) m: FSD value
Note 1: Set f
SYN
to 12MHz or lower.
Table 2.7.2. Example of Setting the Frequency Multiply Register (FSM)
f
PIN
1 MH
Z
2 MH
Z
4 MH
Z
6 MH
Z
8 MH
Z
12 MH
Z
FSM Value
Dec (Hex)
23 (17
16
)
11 (0B
16
)
5 (05
16
)
3 (03
16
)
2 (02
16
)
1 (01
16
)
48 MH
Z
48 MH
Z
48 MH
Z
48 MH
Z
48 MH
Z
48 MH
Z
f
VCO
f
VCO
12.00 MH
Z
8.00 MH
Z
16.00 MH
Z
(Note 1)
6.00 MH
Z
187.50 kH
Z
FSD Value
Dec (Hex)
1 (01
16
)
2 (02
16
)
2 (02
16
)
3 (03
16
)
127 (7F
16
)
48 MH
Z
f
SYN
Table 2.7.3. Example of Setting the frequency synthesizer divide register (FSD)
Note 1: f
SYN
=f
VCO
/(m+1) when FSCCR4=1 and m=2.
Содержание M16C FAMILY
Страница 12: ...Chapter 1 Hardware...
Страница 13: ...See M30245 group datasheet...
Страница 14: ...Chapter 2 Peripheral Functions Usage...
Страница 303: ...THIS PAGE IS BLANK FOR REASONS OF LAYOUT...
Страница 304: ...Chapter 3 Examples of Peripheral Functions Applications...
Страница 340: ...Chapter 4 External Buses...
Страница 361: ...THIS PAGE IS BLANK FOR REASONS OF LAYOUT...
Страница 362: ...Chapter 5 Standard Characteristics...
Страница 369: ...1753 Shimonumabe Nakahara ku Kawasaki shi Kanagawa 211 8668 Japan M30245 Group REJ09B0340 0200 User s Manual...